Russian Nouns Aliveness

Nouns Aliveness

Russian nouns are classified as animate (alive) or inanimate (not alive). This is called "aliveness" or "animacy" and mainly affects grammar in the Accusative case.

What counts as animate?

Animate (одушевлённые):

Humans: челове́к, студе́нт, ма́ма
Animals: соба́ка, кот, пти́ца
Sometimes fictional beings: ро́бот, при́зрак

Inanimate (неодушевлённые):

Objects: стол, кни́га, телефо́н
Abstract concepts: иде́я, любо́вь
Plants are usually treated as inanimate: де́рево, цвето́к

Why it matters (Accusative case)

Knowing the aliveness is important for the declension of nouns and adjectives. You always need it when declining a male noun or a plural form. In all following examples we will use sentences with verbs that require the Accusative case.

Accusative Singular (for masculine Nouns)

For masculine (singular), the Accusative will be the same as either Nominative or Genitive, depending on the aliveness.

Inanimate → Nominative
(I see the table.) → This Accusative is the same as the Nominative.
Animate → Genitive
(I see the brother.) → This Accusative is the same as the Genitive.

Here on OpenRussian you can also see it in the declension tables.

For inanimate nouns, the Accusative is always the same as the Nominative, for example in год (year), глаз (eye), ве́чер (evening).
For animate nouns, the Accusative is always the same as the Genitive, for example in сын (son) or инжене́р (engineer) or пило́т (pilot).

Feminine nouns

Just for comparison, here is how for female nouns nothing changes:

(animate), (inanimate) → no visible difference.

Accusative Plural (all gender nouns)

For Plural (all genders) there is an equivalent rule for Accusative:

Inanimate → Nominative Plural
(I see the tables.) → This Accusative Plural is the same as the Nominative Plural.
Animate → Genitive Plural
(I see the women.) → This Accusative Plural is the same as the Genitive Plural.

Accusative for Adjectives

For Adjectives, the same rule applies: In Accusative they follow the noun and change depending on animacy, for male nouns and all plurals.

Masculine (singular)
Inanimate → Nominative form
(I see a new table.)
Animate → Genitive form
(I see a new student.)
Plural (all genders)
Inanimate → Nominative Plural
(I see new tables.)
Animate → Genitive Plural
(I see new students.)
Feminine (singular) no change
The form is fixed, so animacy does not change it:
(I see a new sister.)
(I see a new book.)

In short: adjectives always agree with the noun, so whenever animacy affects the noun, it also affects the adjective.

Some exceptions

Words like труп (corpse) → grammatically animate.
Words like наро́д (people as a group) → inanimate.
Some creatures or characters depend on meaning/context.

Summary

If it is a person or animal it's animate/alive, else inanimate/not alive.
Sets Accusative form for male nouns and plurals: Nominative for inanimate and Genitive for animate.